Spring suspension for vehicles



' w. s. HARLEY E1' AL SPRING su'sPEms'IoN` FOR v'EHIcLEs w S. HARLEY El' AL sPING SUSPENSION FOR VEHICLES 2 Sheets-Shag?. 2

Filed June 29, 1925 M/z'am 45.' Har/eg Patented Aug. 3, 1926.

.UNITED STATES PATENT oFFicE'-,

WILLIAM S. HARLEY AND ARTHUR R. CONSTAN'IINE, OF MILWAUKEEyWISCONSIN,

ASSIGNORS TO HARLEY-DAVIDSON MOTOR COMPANY, 0F MILWAUKEE, WISCON- SIN, A. CORPORATION OF WISCONSIN.

SIRINGKSUSPENSION FOR VEHICLES.

Application filed June 29, 1923.

This invention relates to a spring suspension for vehicle bodies.

, It is particularly adapted for'supporting motorcycle side cars but may be used for supporting the bodies `of other vehicles.

Heretofore, in motorcycle side car construction, it has been the practice to employ two distinct sets of springs for thev front and rear of the side car body. These springs were mounted on the side car frame near the front and rear thereof and were of necessity comparatively short. The action of the side car body when so supported was such that the forward end of the car body responded to the irregularities to which the front wheel of the motorcycle was subjected and the rear of the car body responded to irregularities to which the rear wheels were subjected, resulting in pitching and irregular motion of the body.

Expressed in other language, side car mountings as heretofore provided have been open to the objection that vibrations communicated to the Wheels have had only a relatively short path tothe body of the side car, and, furthermore, have had a path through which said vibrations were communicated with such directness that the cushioning effects of the springs have left much to be desired.

It is an object of the present invention to provide a mounting` means for a side car in which shocks communicated to the wheels must travel through a relatively long spring path before being communicated to the body of the side car, which spring path, moreover, is so disposed relative to the wheels of the motorcycle 'and to the body of the side car that said shocks are communicated only very indirectly.

A further object is to provide a spring suport for a side car which is separated at a point closely adjacent to the rear axle of i the motorcycle, whereby shocks communicated to the axle will be substantially ineffective in communicating vibration to the 'side car in a forward or rearwardjdirection and which will eifectually cut down communication of suchshocks in a vertical direction.

Serial No. 648,504.

that said shocks will be effectually smoothed out before reaching said side car. e Y

A further object of this linvention is to provide an improved spring suspension Laatstewhich will substantially eliminate pitching v of the vehicle body.

Another object isto provide a spring suspension for vehicle bodies of simplifiedV construction. Y

. Another object is to provide a'spring support for vehicle bodies of increased effectiveness for absorbing the shocks incident to travel. Y v Another object is to provide a spring support for a vehicle bodywhich willA enable the use of realtively'long springs. i

Another object is to provide means for dampening the vibrations of the supporting springs.

Other objects and advantageswill hereinafter appear. Y

In accordance with this invention aspreferably embodied, the vehicle body is supported'by a single pair leaf springs supported adjacent the rear axle of the vehicle.

In order to more fully explainv the invention and a way in which it may be embodied, the accompanying drawings will be described.

Fig. l is a plan of a motorcycle side car frame and spring suspension with the side car removed.

Fig. 2 is an elevation of the motorcycle side car frame and spring support, and

Fig. 3 is a perspective view of the spring carried by the rear axle 3 of the side car frame.

U-bolts 10 pass over the springs and through suitable openings 11 in the spring seats and have nuts 12 threaded on the lower ends thereof to secure the springs to the spring seats. Y

Eachspring seat comprises a hub 13, the supporting surface 14 and a reinforcing rib 15. The hub 13 passes overth-e rear axleand is brazed thereto, making the seatsubstantially integral with the axle.

Of course, if desired, other forms ofspring seats may be used.

In the embodiment illustrated, the. supporting surface 14 extends forwardY of the rear axle to bring. the center, of the spring more nearly under-the center of gravityof.

theload .and4 to permit the. use of relatively long springs.y The locationof thespring seat, however, may be varied te suit vehiclebodies andsupportingframes of differentJ designs.

The forward ends of the- Springs are` providedv with. shackles 16 which passv aroundI the ends of the crossbar 4. p

vThe rear ends of the springs are secured to shackle bolts 1.7 carrying llinlrsl in` which 'they ends.1i9'of the rear. crossbar 5 are care ried. Y

The. rear cross. rod-5 is bentforwardly at 20 to.pass` under therearof the sidecar bod-y y and` has bolt opening21 therethroughjfor securing the side car body thereto.

The forward end. of the'. car bodyk is boltedto the forward crossbar 4, bolt openings V22 being provided for the' purpose.

lVhen apassengerenters or leavesthe side car through the door 23, theentire'weig-htof the passenger is supported by the forward endv of the spring. K n n The fo'rward end of the spring-is, therefore,l provided with an extra leaf 24 teincrease the strengththereof. This leaf 24v StrapV 26,.fastened to the underside of the.

car body by a clamping plate 27, passes partially` around the rear axle. 3 and. is connected to the front bar 28 of theI side car frame through a helical' spring 29 and an adjustable member 30.

Arelatively large surfaeeof frictional. engagement of the strap. withf the axleis pro vided4 to create a snubbing action.

Spring, 29 insures that the strap 26gwill be retained in engagement with. theaxle 3 at all times. 1

The strap member 30. is provided with a plurality of openings 31 for engagement with the pin82 carried by the frame member 28, whereby the tension of the spring 29 1 long springs land 2, so that there is practically no tilting of the car body in response thereto..

l/Vhen the rear wheel strikes the obstructionor depression, there is no twisting ofthe rear axle and the movement of `the body.y in response to the movement of. the rear .axle

2, due to their length andV lowperiod of vi# bration, absorb a large portion of the shock` in transmittinglthe motion to the side. car

body, and the check strap v.26, snubbingt,

around the, axle 3 prevents.- undue ,jouncing of the body. l

Thus, as the motorcycle travels overthe surface of the` road, having slight vertical movement. in response yto the irregularities over. which the rear wheels pass but having nopitching motion in response to the irregu.-4 i

lar movement ofthe. front wheel.

Expressed in other language,y thefunc.- tions of the improved construction above de'- scribed may beoutlined` as follows. leaf spring 2, it will be noted, is relatively long comparedto the wheely base of. .the motorcycle; Moreover, eachl of said leaf springs 2 is relatively flat. Each. leaf spring 2 is supported at a single point sube.. It willsbe.

stantially. midwayv ofl its# length'. obvious, of course, that inra construction which is not effectually cushionedy shocksv in a vertical .direction communicated to. the

Eachv front wheel willV result in a. pitchingaction of the side car, producing a very uncomfortable oscillating-action of thebaclr. rest of. said side car.

rIn prior constructions thisl oscillatingy effect. has been very annoying tol a passenger in the. sidey car. According to the present invention, shocks in a vertical direction communicated to thefront wheelof the motorcycle must be vtransmitted byy way of the axle reason of the factl that A The Jtime element is impor-- lit of their length. As explained above in con-` nection with shocks communicated from the front wheel, said shocks have a relatively long path before being communicated to the side car and are communicated in a direction substantially transverse to the length of said springs, whereby said shoclrsare communicated only very indirectly. The present construction involves substantially no oscillation of the back rest cf the side car, which, as referred to above, has been so annoying in prior constructions.

Of course, this invention is susceptible of other adaptations and modifications.

l. In a motorcycle, in combination, the front and rear Wheels of said motorcycle, the body of said motorcycle, and leaf springs Ifor supporting said body, said leaf springs comprising relatively flat members which are relatively long compared to the Wheel base of said motorcycle, said leaf springs being supported substantially midway of their length solely from the rear axle of said motorcycle and having their ends connected to said side car and forming` the sole support therefor.

2. In motorcycle side car supporting means, a rear axle, relatively long leaf springs disposed transversely of said axle and supported solely by said axle, the region of such support being substantially midway of the length of said leaf springs, the extremities of said leaf springs forming connecting means for supporting a motorcycle. side car.

3. In motorcycle side car supporting means, a rear axle, relatively long leaf springs disposed transverselyl of said axle and supported solely by said axle, the region of such support being substantially midway of the length of said leaf springs, the extremities of said leaf springs lforming connecting means for supporting a motorcycle side car, each of said leaf springs having its forward portion of greater strength than the rear portion thereof.

' 4.. In combination, the rear axle of a motorcycle, a side car and spring supporting means for said side car, said supporting means comprising longitudinally extending leaf springs disposed transversely to said rear axle, said leaf springs having their sole support substantially midway of their length upon said rear axle.

5. A spring support for a motorcycle side car body comprising a pair of semi-elliptical springs mounted adjacent the rear axle of the motorcycleside car frame and forming the sole support for said body, and means Vfor dampening the vibration of said body;

6. Shock absorbing means for a motorcycle side car body comprising a pair of relatively long leaf springs forming the sole support for said body, and snubbing means for dampening the vibration of said body.

7. The combination with a motorcycle, of

a side car frame, a side car body, and rsnub-r bing means attached to said body and passing around one of the members of said frame to prevent excessive vibration of said body.

8. The combination with a motorcycle, of

a side car frame, a side car body,`snubbing means attached to said body and passing around one. of the members of said frameV to prevent excessive vibration of said body, and resilient means 'for maintaining said snubbing means in engagement with said member. p

9. In combination, a car body, a frame therefor, said frame comprising an axle and a pair of springs secured thereto, said car body being supported by said springs, and a strap secured to said car body and arranged for cooperation with said frame to dampen the vibrations of said springs.

10. In combination, a car body, a frame therefor, said frame comprising an axle and a pair of springs secured thereto, said car body being supported by said springs, a strap secured to said car body' and arranged for cooperation with said frame to dampen the vibrations of said springs, and means to vary the eect of said strap.

11. In combination, a car body, a frame therefor, said frame comprising an axle and a pair of semi-elliptical springs secured thereto, said car body being supported by said springs, and a strap secured to said car body and cooperating with said axle to dampen the vibrations of said springs.

VILLIAM S. HARLEY. ARTHUR R. CONSTANTINE.

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